Friction draft-gear.



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FRITION DRAFT GEAR. APPLICATIQN FILED AUG. 13, 5917;

Patented Jan. 1,1918.

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i UNITED STATES Param: orar/oa j CLIFTON W. SHERMAN, OVF BUFFALO, NEW YORK.

FRICTION DRAFT-GEAR.

Bpecicatlon of Letters Patent.

Patented Jan. 1, 1918.

Original application filed April 23, 1914-, Serial No. 833,598.' Divided and this application filed August 13,

To all 'whom t may concern:

it lrnown that-l, CLi'r'roN YV. Sinni* MAN, a citizen vof the United Stat-cs resid.- ing at Buffalo, in the county of Eric anoI State of New York, have invented new and `useful Improvements in Friction Draft- Gears, ot' which the following is a specification.

This invention relates to 'friction dra't't gears such as are used in rnilway cars 'for relieving the same from the shrmlc. jar und strains While couplingr and drawin 11 the cars,

The object ci' this; invention is to provide a draft rear oi this charzlcter in which thc frictional surfaces are more ei'icctive and the frictional engagement ci" the frictional elements is distributed more uniformly over these elements. ,i

This application a division oan appli cation filed. by myself itpril 23,1914, Serial ln the accompanying drawings:

Figure 1. is a `frapnuentary horizontal longitndinal section showing form of friction draft gear embodying my invention and showing the parts in the position which they occupy when the gear is in normal position.

Fig. 2 is a vertical transverse section thereofw taken in line 2-2, Figul. 3 is-a View; Similar to Fig. 2 but showing the parts in the position which they occupy when th'e gear is suhj ectcd to hailing or pulling;r blow.

Similar characters of reference indicate corresponding parts in the several yicws.

51 represents a friction cylinder arranged lengthwise between two draft sills 52 and engaging 'its rear end Wthrearstope 53 on the silla. 73 represents a front follower arranged transversely between the sills andengaging its front side with two front stops 54 on the sills. 6 represents the `coupler having a draw har 84; engaging with the front side of the front follower and connected 'with a yoke which extends le'ngtl'xwise of the upper and lower sides of 'the cylinder and engaging with the warhead l5G thereof: 57 represents two friction shoes engaging their trmisi'f'erscly outer sides with the hine ofl'the cylinder and 'noiided-'aft its front and cords i nined faces 58, t9., the rear tocca being iucl'ned at an angle relatively' to the ani; the 'cylinder 'which is more acuto than shoes are ar? t'. L the i ed tno two sect-iena ed? of a divided Serial No. 185,887.

or split wedge each of which is provided at opposite ends of itsy transversely outer side with front andl rear inclined faces 62, 63 which are of they corresponding anni@ as the front and. rear inclined tacos ot the com panion friction shoe and are adapted to engage therewith successively. Those wedge sections are yicldingly held in a separated position crosswise of the cylinder hy trans rcrsely operating spring means Which prefcrzihly comprise two transverse springs 64 arranged between the opposing longitmlinai faces oi these wedge sections and Seated at their opposite ends in recesses or pockets formed in these sections. represents a heavy main spring .interposed between the rear head of the cylinder and `the rear ends of the friction. shoes and G6 a comparatively ,light releasing spring' interposed between said rear cylinder head and the rear ends of said Wedge sections,

In the normal position of the parts the Wedge sections are separated enclin the outermost position in which the rear inclined faces of these sections engage with the rear inclined faces of the shoes and the front inclined faces of those sections are out of engagement with the front inclined faces of the shoes, as shown in Fig. 1.

During the initial part of the inward movement of the wedge sections under a hinting or pulling blow, the friction shoes are held practically at rest by thc 'resistance of the fhain spring 65 and thefrictional en gagement of the saine due to the lateral pressure of the springs 64. This enables the weide-ing engagement of the rear or inner cooperating faces of the shoes and wedge sections which operate'on a relatively acute angle to press the shoes with great force against the cylinder' and produce a powerful ,si-ripping' engagementbetwcen these parts. Then the wedge sections have moved inwardly far enough to cause the acute inner inclined 'faces of the saine tdmovc, these sections toward each other so tha t they neaily engage cach other then the outer or front inclined faces of the shoes and Wedge sec tions engage each other, as shown in Fig. causing the wedge sections to engage each other5 and as the angle of the last mentioned facesis less acute or more blunt the Same have less tendency to further spread, `the shoes but more of a tendency to pushvthe f laminaat) of the shoes is resisted by the loiiigitudinal springs and the frictional contact between the cylinder and shoes7 an effective cushioning ofthe blow against the car is produced both when pulling or pushing the same.

I claim as my invention:

1. A frictional draft gear comprising a member having a friction surface, a set of friction shoes in frictional engagement with said member, a wedge movable forvardly and rearwardly between the several shoes, longitudinally operating spring means which resist the rearward movement of said friction shoes and wedge, and transversely operating spring means which are exed by the rearward movement of said wedge relatively tosaid shoes and cause the latter to be pressed transversely against said friction member, said wedge having an inclined rear part which engages a similar rear part on said shoes and an inclined front part which engages a similar front part on said shoes, the angle of wedging engagement of 4said rear parts being more acute than the angle of wedging engagement of said front parts.

2. At friction draft gear eomprisin a friction member having a friction sur ace, a set of friction shoesengaging frictionally with said member, a Wedge movable forwardly and rearwardly between'said shoes and composed of a plurality of sections, longitudinally operating spring means resisting the rearward movement of said shoes and wedge, and transversely operating spring means arranged between said wedge sections and resisting movement. of said wedge sections transversely toward each other, those parts ofsaid wedge sections and shoes nearer the longitudinally operating spring `means having a wedging engagement the angle of which is comparatively acute and those parts of said Wedge sections and shoes remoter from said longitudinally operating spring means having a wedging engagement the angle of whichV is comparatively obtuse.

CLIFTON W. SHERMAN. 

